usb: otg: notifier: switch to atomic notifier

most of our notifications, will be called from IRQ
context, so an atomic notifier suits the job better.

Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/otg/nop-usb-xceiv.c b/drivers/usb/otg/nop-usb-xceiv.c
index 8acf165..c1e3600 100644
--- a/drivers/usb/otg/nop-usb-xceiv.c
+++ b/drivers/usb/otg/nop-usb-xceiv.c
@@ -132,7 +132,7 @@
 
 	platform_set_drvdata(pdev, nop);
 
-	BLOCKING_INIT_NOTIFIER_HEAD(&nop->otg.notifier);
+	ATOMIC_INIT_NOTIFIER_HEAD(&nop->otg.notifier);
 
 	return 0;
 exit: